R&R Other Project Information - Oxidative Stress and Oocyte Development 6. Project Summary/Abstract The health of adults, neonates, fetuses, and embryos all depend upon normal development of the oocytes from which they arise. Therefore, defining biomarkers of oocyte quality will prove extremely invaluable in not only the identification of determinants of oocyte health but also the diagnosis and management of human infertility with assisted reproductive technologies. A multitude of factors are likely to influence the development of oocytes, and our proposal focuses on oxidative stress, a cellular and biochemical state that has been grossly-understudied thus far in the ovary. Similarly, little is known about the pro-/anti-oxidant balances during stages of antral follicular development at a time when oocytes undergo critical maturation steps and acquire developmental competence. Innovatively, our proposal centers on the multiple cellular and extracellular compartments that make up antral follicles, namely granulosa cells, follicular fluid, and cumulus-oocyte-complexes. The specific aims of this project are to: (1) characterize the exogenous and endogenous oxidative stress status of bovine antral follicles, with specific attention onto potential patterns of temporal and spatial regulation; and (2) evaluate the dynamics and functional roles of pro-/anti-oxidant balances during the culture of granulosa cells and in vitro maturation of cumulus-oocyte-complexes. Towards this goal, we will employ: (i) a battery of oxidative stress assays (measuring both pro-oxidants and several carefully-selected antioxidant enzymes); and (ii) in vitro culture conditions that we will use to exogenously manipulate relative levels of oxidative stress (either increased or decreased). Taken together, studies proposed herein will permit an enhanced appreciation of the relative importance of oxidative stress during oocyte development. In addition, our findings will enable not only clinical prevention of oxidative damage in oocytes but also the identification of novel markers of oocyte quality and maturation conditions, all in dire need of optimization so that fertile and infertile couples alike can be assured healthy embryos, fetuses, and babies. R&R Other Project Information - Oxidative Stress and Oocyte Development 7. Project Narrative Using a clinically-relevant animal model, this proposal aims to improve our basic understanding of factors that may influence the quality of oocytes. Towards this goal, we will investigate the oxidative stress systems that prevail in all of all the compartments making up the ovarian follicle. We will then be able to better define the milieu within which an oocyte acquires its normal ability to support the complete development of a healthy embryo, fetus, and eventually adult. These findings will enhance our ability to detect and produce oocytes of optimal quality, thereby providing critical foundations for the improvement of female reproductive health. [unreadable] [unreadable] [unreadable]